code: def forward(self, x):
      x = self.bn1(x)
      x = self.relu(x)
      x = self.conv_bn_relu(x)
      out = self.conv(x)
  
      if self.scale_factor is not None:
          out = F.interpolate(
              out, scale_factor=self.scale_factor, mode="bilinear"
          )
      return out
  
imports: import paddle
  import paddle.nn
  import paddle.nn.functional
  from paddleseg.cvlibs import manager, param_init
  from paddleseg.models import layers
  from paddleseg.utils import utils
label_desc: Use image node_id 2 for calling the DDRNetHead obj's underlying member method code with example usage: obj.forward(x) and returns: out